Pant-type absorbent articles include a pant-shaped chassis structure and an absorbent core component integrated with the chassis. A major objective when designing pant articles is to make them resemble ordinary underwear as closely as possible. Hence, absorbent articles such as pant diapers, sanitary pants and incontinence pants are designed to fit comfortably and snugly about the wearer. It is desirable that the articles are capable of being pulled up and down over the hips of the wearer to allow the wearer or caregiver to easily remove a soiled article and to replace it with a new clean one. For these reasons, the article chassis is usually made of a material that is elastically stretchable, at least in the areas intended to be applied over the wearer's hips. Furthermore, it is desirable that the chassis surrounding the absorbent parts of the pant-type article is permeable to air and vapour, i.e. that it is breathable. A breathable article prevents moisture from remaining on the skin of the wearer and is more comfortable and less warm to wear than a non-breathable article. It is also beneficial if the article is soft, smooth and textile-like, so that it does not chafe the skin of the wearer and so that it resembles ordinary underwear as closely as possible.
Moreover, it is important that the absorbent pant article can be pulled up over the hips of a wearer without rupturing. A common problem is that the wearer or the caregiver tears the pant by inadvertently poking the fingers through the material when trying to get a good grip for pulling up or removing the pant.
A previously used elastic material for pant articles is a laminate comprising an elastic film sandwiched between two layers of non-elastic nonwoven. In order to render the laminate elastically stretchable, it is subjected to an activation treatment. A three-layer, activated laminate is disclosed in International Patent Application No. WO 03/047488. The activated laminate is produced by incrementally stretching an elastic film layer between two non-elastic cloth-like layers. Incremental stretching is carried out by passing the laminate between intermeshing gear rollers. Activation of elastic laminates by incremental stretching is also disclosed in U.S. Pat. Nos. 5,143,679, 5,156,793 5,167,897, 5,422,172, 5,592,690, 5,634,216 and 5,861,074. The non-elastic cloth-like layers are fully or partially broken or torn during the activation process so that the elasticity of the laminate after activation is mainly governed by the elasticity of the elastic film layer. In the three-layer laminate in WO 03/047488, the non-elastic layers are completely broken so that the elasticity of the activated laminate is substantially the same as the elasticity of the elastic film layer.
The disclosed laminates have good comfort properties and are soft, textile-like, breathable and elastic. However, a major disadvantage with the known laminates is that the activation process at least partially breaks and destroys the cloth-like layers resulting in a material having decreased tensile strength and puncture resistance. When used as a chassis component in a disposable pant article, the material is easily torn when exposed to the forces arising when putting on or pulling off the pant article. This tearing problem is particularly pronounced for female wearers or caregivers who often have long fingernails that may penetrate and destroy the pant material.
In order to overcome the problem with low resistance to the stresses arising during use of an absorbent article including an elastic laminate, it has been suggested in US 2005/0101216 A1 to form an elastic laminate from an elastic film and a creped nonwoven. By using a creped nonwoven, the laminate will have the soft and lofty properties of the creped, bulky nonwoven. Moreover, the creped nonwoven is also said to render the laminate elastic as the nonwoven is extensible in the direction of creping. The use of a creped nonwoven is offered as an alternative to activation by incremental stretching. Hence, US 2005/0101216 A1 teaches that by using a creped nonwoven, the harsh activation treatment with its concomitant detrimental effect on the strength of the nonwoven web can be avoided.
However, although the creped nonwoven used in US 2005/0101216 A1 provides the laminates with some degree of elasticity, the elastic properties of the laminates are still severely limited by the extensibility of the creped nonwoven.
Hence, there still exists a need for an elastic laminate combining high tensile strength, softness, flexibility and puncture resistance. There is also a need for a pant-type absorbent article having a chassis with elastic panel portions having high tensile strength, softness, flexibility and puncture resistance.
Accordingly, an object of the invention is to provide an improved elastically stretchable laminate for use in disposable pant-type absorbent articles. Another object of the invention is to provide a textile-like disposable pant-type absorbent article having improved tensile strength and puncture resistance in combination with softness and flexibility. A further object of the invention is to offer a simple and economical method for the production of an elastically stretchable laminate having high tensile strength and textile-like appearance.